A series of chiral linear and macrocyclic bridged pyridines has been prepared starting from pyridine-2,6-dicarbonyl dichloride (2). The coupling of 1 with D-alanyl methyl ester gave 2,6-bis-D-alanyl pyridine methyl ester (3). Hydrazinolysis of 3 with hydrazine hydrate afforded bis-hydrazide 4. The latter was reacted with thiophene-2-carbaldehyde, phthalic anhydride or cyclohexanone to afford bi...

A low loading of a quinine-derived squaramide efficiently catalyzes the triple-domino Michael/aza-Henry/cyclization reaction between 1,3-dicarbonyl compounds, β-nitroolefins, and aldimines to provide tetrahydropyridines bearing three contiguous stereogenic centers in good yields, excellent enantiomeric excesses, and up to high diastereomeric ratios.

A practical and efficient palladium-catalyzed direct allylation of β-dicarbonyl compounds with both cyclic and acyclic Morita-Baylis-Hillman (MBH) alcohols, using Et3B as a Lewis acid promoter, is described herein. A wide range of the corresponding functionalized allylated derivatives have been obtained in good yields and with high selectivity.

An efficient catalytic asymmetric hetero-ene reaction of 5-methyleneoxazolines with 1,2-dicarbonyl compounds (including α-ketoesters and glyoxal derivatives) was realized using Ni(II)-N,N'-dioxide complexes as the catalysts. It provides a rapid, high yielding (up to 99%) route for the preparation of 2,5-disubstituted oxazole derivatives in a highly enantioenriched form (up to >99% ee) under mil...

An efficient silver-catalyzed oxidative cyclization of acrylamides with 1,3-dicarbonyl compounds is described. It proceeds through a tandem radical addition/cyclization process, in which two new C-C bonds were formed. Furthermore, the same concept can also be extended to the reaction of easily available ketones and acrylamides.

Condensation of 5,6-diamino-4,7-phenanthroline with glyoxal provides 1,4,5,12-tetraazatriphenylene in quantitative yield. This procedure avoids the 50% loss of product inherent in previous methods. Derivatives were also prepared by using alpha-dicarbonyl compounds other than glyoxal. Additional derivatives were prepared from 1,4,5,12-tetraazatriphenylene-2,3-dicarbonitrile, produced by condensa...

A chiral tridentate ketimine P,N,N-ligand has been successfully applied in the copper-catalyzed enantioselective propargylic substitution of propargylic acetates with a variety of β-dicarbonyl compounds, in which excellent enantioselectivities (up to >99% ee) and high yields have been obtained.